Unique footage of a pilot whale expelling its placenta off the coast of Shetland in 2019 has been revealed for the first time.

The footage, taken by drone operator Nick McCaffrey, shows the animal in the Yell Sound between mainland Shetland and the island of Yell.

Mr McCaffrey did not realise how rare the footage was until he shared it with Emily Hague, a marine mammal researcher at Heriot-Watt University in Edinburgh.

They say the clip gives insight into the lives of pilot whales.

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Mr McCaffrey said: “I knew at the time I had witnessed something significant, but it took a moment to realise that I was looking at a pilot whale placenta. After that, the behaviours I was observing became a whole lot more intriguing.”

Ms Hague said: “Drone footage is helping us capture moments that would be impossible to see from land or boat, giving us a new insight into the underwater world.

The Herald: Still from footage of a pilot whale expelling its placentaStill from footage of a pilot whale expelling its placenta (Image: Nick McCaffrey)

“Until now, knowledge of where pilot whales have their calves was extremely limited. In fact, we don’t have much understanding of where many marine mammals give birth.

“We do know that whales and dolphins tend to expel the placenta within 12 hours of giving birth, so we can be pretty sure that this pilot whale had its calf in UK waters.

“Understanding marine mammals’ behaviour, knowing where they mate and reproduce, can help us know where to target protection of the marine environment so that they can thrive.”

Pilot whales are the second largest member of the oceanic dolphin family, behind the orca, and can measure up to 6.3 metres in length.